LayoutRect.cpp   [plain text]

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#include "config.h"
#include "LayoutRect.h"

#include "TextStream.h"
#include <algorithm>

namespace WebCore {

LayoutRect::LayoutRect(const FloatRect& r)
    : m_location(LayoutPoint(r.location()))
    , m_size(LayoutSize(r.size()))
{
}

bool LayoutRect::intersects(const LayoutRect& other) const
{
    // Checking emptiness handles negative widths as well as zero.
    return !isEmpty() && !other.isEmpty()
        && x() < other.maxX() && other.x() < maxX()
        && y() < other.maxY() && other.y() < maxY();
}

bool LayoutRect::contains(const LayoutRect& other) const
{
    return x() <= other.x() && maxX() >= other.maxX()
        && y() <= other.y() && maxY() >= other.maxY();
}

void LayoutRect::intersect(const LayoutRect& other)
{
    LayoutPoint newLocation(std::max(x(), other.x()), std::max(y(), other.y()));
    LayoutPoint newMaxPoint(std::min(maxX(), other.maxX()), std::min(maxY(), other.maxY()));

    // Return a clean empty rectangle for non-intersecting cases.
    if (newLocation.x() >= newMaxPoint.x() || newLocation.y() >= newMaxPoint.y()) {
        newLocation = LayoutPoint(0, 0);
        newMaxPoint = LayoutPoint(0, 0);
    }

    m_location = newLocation;
    m_size = newMaxPoint - newLocation;
}

void LayoutRect::unite(const LayoutRect& other)
{
    // Handle empty special cases first.
    if (other.isEmpty())
        return;
    if (isEmpty()) {
        *this = other;
        return;
    }

    LayoutPoint newLocation(std::min(x(), other.x()), std::min(y(), other.y()));
    LayoutPoint newMaxPoint(std::max(maxX(), other.maxX()), std::max(maxY(), other.maxY()));

    m_location = newLocation;
    m_size = newMaxPoint - newLocation;
}

void LayoutRect::uniteIfNonZero(const LayoutRect& other)
{
    // Handle empty special cases first.
    if (!other.width() && !other.height())
        return;
    if (!width() && !height()) {
        *this = other;
        return;
    }

    LayoutPoint newLocation(std::min(x(), other.x()), std::min(y(), other.y()));
    LayoutPoint newMaxPoint(std::max(maxX(), other.maxX()), std::max(maxY(), other.maxY()));

    m_location = newLocation;
    m_size = newMaxPoint - newLocation;
}

void LayoutRect::scale(float scaleValue)
{
    scale(scaleValue, scaleValue);
}

void LayoutRect::scale(float xScale, float yScale)
{
    if (isInfinite())
        return;
    m_location.scale(xScale, yScale);
    m_size.scale(xScale, yScale);
}

LayoutRect unionRect(const Vector<LayoutRect>& rects)
{
    LayoutRect result;

    size_t count = rects.size();
    for (size_t i = 0; i < count; ++i)
        result.unite(rects[i]);

    return result;
}

IntRect enclosingIntRect(const LayoutRect& rect)
{
    // Empty rects with fractional x, y values turn into non-empty rects when converting to enclosing.
    // We need to ensure that empty rects stay empty after the conversion, because the selection code expects them to be empty.
    IntPoint location = flooredIntPoint(rect.minXMinYCorner());
    IntPoint maxPoint = IntPoint(rect.width() ? rect.maxX().ceil() : location.x(), rect.height() ? rect.maxY().ceil() : location.y());
    return IntRect(location, maxPoint - location);
}

LayoutRect enclosingLayoutRect(const FloatRect& rect)
{
    LayoutPoint location = flooredLayoutPoint(rect.minXMinYCorner());
    LayoutPoint maxPoint = ceiledLayoutPoint(rect.maxXMaxYCorner());

    return LayoutRect(location, maxPoint - location);
}

FloatRect encloseRectToDevicePixels(const LayoutRect& rect, float pixelSnappingFactor)
{
    FloatPoint location = floorPointToDevicePixels(rect.minXMinYCorner(), pixelSnappingFactor);
    FloatPoint maxPoint = ceilPointToDevicePixels(rect.maxXMaxYCorner(), pixelSnappingFactor);

    return FloatRect(location, maxPoint - location);
}

TextStream& operator<<(TextStream& ts, const LayoutRect& r)
{
    // FIXME: These should be printed as floats. Keeping them ints for consistency with previous test expectations.
    return ts << snappedIntRect(r);
}

} // namespace WebCore